Solahart 181J180lt Roof Top Solar System

The 181J solar water heater is specifically designed to provide economical service in medium to high solar gain areas, and is suitable for frost prone or harsh water quality areas. The smaller volume of the 181J makes it ideal for applications where low volumes of solar hot water are required, e.g. small units or retirees.

Key Features

The Solahart J Series is a roof mounted, closed circuit solar water heater specifically designed to provide economical service in medium to high solar gain areas. It is recommended for use in frost or poor water chemistry areas.

The J Series features Solahart's revolutionary multi-flow collector to extract the maximum amount of energy from the sun. This is used to heat the Hartgard fluid in the collector which rises into the heat exchanger where the heat is transferred to the water inside of the tank. The ceramic lined tank has a protective anode and the SP Free Heat series features additional protection.

* For safe access and servicing, a space equal to the tank length should be left on the water connection end of the system and 1m (40in) should be left on the three other sides of the installation. ‡HartStat OTP is mandatory on these models in Australia and New Zealand. Systems (if installed with a HartStat OTP system) can be installed as a solar preheater with an inline Solahart gas booster water heater. Refer to the Solahart gas booster specification sheet for further details on the gas booster.

Collectors SPA2000

Aperture area

1.8 m2

Dimensions

Length

1996 mm

Width

1043 mm

Height

82 mm

Capacity

3.8 litres

Weight Empty

47 kg

Weight Full

51 kg

Working Pressure

no OTP

80 kPa

with OTP

170 kPa

Absorber Surface

Black polyester powder coat

Absorber/Riser Material

steel

Number of Risers

35

Frame Material

aluminium

Insulation Material (Base)

38 mm polyester blanket

Glass

3.2 mm tempered low iron

Water Supply

TPR Valve Setting

1000 kPa

ECV* Setting

850 kPa

Maximum Supply Pressure

With ECV

680 kPa

Without ECV

800 kPa

Water Connections

Cold

Rp 3/4

Hot

R 1/2

*Expansion Control Valve.

Electric Boost Specifications

Heating Unit Type

Copper sheath immersion element

Supply Voltage

220 V - 250 V

Recovery Rate @ 240 V and Temperature Rise of:

RatingkW

CurrentAmps

30°Clitres/hour

40°Clitres/hour

50°Clitres/hour

1.8

8

51

39

31

2.4

10

68

52

41

3.6

15

103

77

62

4.8

20

137

103

83

How Roof Top Solar Systems Work

Solar Operation

The 181J solar system has its vitreous enamel lined solar storage tank installed on the roof directly coupled to the solar collectors. In the Closed Circuit Series, heat is absorbed by the collector and passed to the ‘Hartgard’ heat transfer liquid inside the collector. As the temperature of the ‘Hartgard’ increases, the hot fluid rises up through the collector by the Natural Thermosiphon Principle, into the heat exchanger jacket around the potable water storage tank. Here, the heat is transferred to the potable water, cooling the ‘Hartgard’ fluid. The cooler fluid is then forced back down into the collectors through the displacement action of further hot fluid rising up into the heat exchanger jacket.

Orientation of Solar Collectors

To help maximise system performance, solar collectors should be installed with an optimum orientation facing true north (in the southern hemisphere) or true south (in the northern hemisphere). Always check for true north or true south using a compass or other suitable device.

To help maximise system performance, solar collectors should be installed with an optimum inclination. This is equal to 90% to 100% of the local latitude angle when collectors are oriented within 60° of true north or true south, and between 10° and 20° if the collectors are oriented between 60° and 90° from the optimum orientation. Generally, improved summer performance is obtained from an angle of inclination less than the optimum angle and improved winter performance is obtained by an angle of inclination greater than the optimum angle. If the angle of inclination varies by 20° from the optimum angle, the solar collectors will receive about 10% less total annual solar radiation.

Frost/Freeze Protection

Solahart Closed Circuit Systems are protected against freezing or harsh water conditions by our exclusive ‘Hartgard’ fluid. ‘Hartgard’ is a blue, non-toxic, propylene glycol fluid which, when mixed with water, provides the Heat Transfer Fluid contained in the solar collectors and the heat exchanger jacket around the tank. ‘Hartgard’ is used to lower the freezing temperature of the Heat Transfer Fluid and so provides protection against freezing (Note: for the correct % of Hartgard in the Heat Transfer Fluid, refer to the section on Frost / Freeze Protection). ‘Hartgard’ is a special food grade solution and is the only solution permitted to be used in the closed circuit systems. Hartgard has been approved by the National Health and Medical Research Council of Australia.

Solar Boosting

In-Tank Boosting

An isolating switch is installed in the electrical meter box for an electrically in-tank boosted model. This should be left switched on to allow the booster heating unit to operate if required. The booster heating unit is for heating the water at times of low solar energy gain, such as during very cloudy or rainy weather, or during the colder months. The booster heating unit will only activate if heating is required and power is available from the switchboard. When the water is below the thermostat setting, the booster heating unit will turn on and heat the water. The booster heating unit will automatically turn off when the temperature of the water reaches the thermostat setting. If the water temperature drops below the setting again the booster will re-activate.

In-Series Gas Boosting

An in-series gas booster (also known as an instantaneous gas booster) can be installed between the solar water heater and the hot outlets in the house. This booster should be permanently active. The booster senses the temperature of the water passing through it: if the water temperature is above its temperature setting it does nothing; if below it will automatically heat the water up to the preset outlet temperature setting. This device ensures hot water delivery for a variety of hot water demands without the need for user intervention while enabling maximum solar energy contribution to the water heating. For more information on this booster, consult the owner’s manual for the product.

Over-Temperature Protection System

The Closed Circuit Series solar water heaters have a means of controlling the maximum temperature of the water in the storage tank. These systems may be installed with a ‘HartStat’ valve located between the hot outlet of the collectors and the inlet to the tank heat exchanger. This valve closes when the tank has reached a sufficiently high temperature, thereby preventing further heat transfer to the tank, and thus limiting its temperature.